Vehicle suspension stabilising arrangement

ABSTRACT

A stabilising arrangement ( 100 ) characterised by a mounting member ( 32 ), at least one forward truck ( 34 ) supporting a forward pair of surface engaging members ( 36 ), and at least one rear truck ( 38 ) supporting a rear pair of surface engaging members ( 40 ), each truck ( 34, 38 ) allowing biased rotation about a, central axis thereof, the forward truck ( 34 ) being mounted on the mounting member ( 32 ) such that it projects forwardly thereof and the rear truck ( 38 ) being mounted on the mounting member ( 32 ) such that it projects rearwardly thereof, and whereby the mounting member ( 32 ) is supported substantially between the trucks ( 34, 38 ) and pairs of surface engaging members ( 36, 40 ). A suspension and steering arrangement is also provided.

FIELD OF THE INVENTION

[0001] The present invention relates to a stablising arrangement.

[0002] The stabilising arrangement of the present invention hasapplication as a suspension and steering arrangement for a vehicle.Further, the suspension and steering arrangement of the presentinvention is intended for use in providing both substantially smoothtransition over uneven terrain and a tight turning circle withoutsliding for the vehicle or conveyance on which it is provided. It isenvisaged that the suspension arrangement of the present invention isparticularly suitable for use on bicycles and motorcycles but is not tobe limited thereto.

[0003] The stabilising arrangement of the present invention further hasapplication as a surface engaging member or foot for use is stabilisingany number of items, including machinery and heavy equipment, on anysurface, although most advantageously on uneven surfaces.

BACKGROUND ART

[0004] Previously, attempts have made to provide either a gliding orskating sensation when utilising a bicycle or similar vehicle orconveyance. In this regard reference may be had to U.S. Pat. No.4,863,182, Australian Patent Application 32359/89 and British PatentApplication 2122557. Each of these documents discloses a bicycle-likeconveyance on which the front-wheel, forks and handle bars have beenreplaced by a single pair of small wheels, for example skateboardwheels, mounted transversely on a single axle. Such an arrangementrequires the rider to steer entirely by shifting their body weight whichin turn acts on a truck supporting the axle of the pair of small wheels.Such an arrangement is difficult to operate and is often dangerous.

[0005] The dangerous nature of prior art arrangements is accentuatedthrough the use of the small pair of wheels, as the small wheels areunable to ride over even small obstacles. As a result, a riderencountering an obstacle at speed may be thrown forward in a dangerousmanner.

[0006] A suspension arrangement that goes some way towards overcomingthe above problems is disclosed in International Patent Publication WO98/57839. This document describes a suspension arrangement for a wheeledconveyance characterised by a mounting member under which is providedtwo pairs of wheels, each pair being mounted on a skateboard-type truck.As the trucks are, mounted directly under the mounting member the wheelsand trucks operate much as they would on a skateboard. An additionalbiasing means is provided which acts to bias the forward pair of the twopairs of wheels upwardly so that obstacles may be mounted safely if therider pulls upwardly on the handlebars, if the suspension arrangement isfitted to a bicycle, thereby “kicking-up” the front pair of wheels tohelp in the mounting of the obstacle.

[0007] Unfortunately, the suspension arrangement of WO98/839 has beenfound not to maintain the “footprint” of the pairs of wheels whenundergoing tight turns, such that one of each pair of wheels has atendency to lift off the ground thereby often causing the wheelsremaining in contact with the ground to skid sideways. Such acircumstance can be dangerous for the rider of the conveyance.

[0008] In the field of heavy machinery, for example cranes and diggingequipment, it is often necessary to stabilise that equipment through theuse of hydraulic rams mounted to the sides thereof. These rams are oftenmounted on extendable arms to spread load and increase stability. Therams further have a ground engaging member or foot pivotally mounted toa lower end thereof. The pivotal mounting is intended to allow someadaptation to the form of the surface on which the equipment is to besupported. However, the provision of a mounting that is pivotal aboutonly a single axis often does not allow sufficiently stable location ofthe foot on the surface, particularly on undulating, loose or slopingsurfaces.

[0009] The suspension and steering arrangement of the present inventionhas as one object thereof to overcome substantially the above problemsof the prior art, or to at least provide a useful alternative thereto.

[0010] The preceding discussion of the background art is intended tofacilitate an understanding of the present invention only. It should beappreciated that the discussion is not an acknowledgement or admissionthat any of the material referred to was part of the common generalknowledge in Australia as at the priority date of the application.

[0011] Throughout the specification, unless the context requiresotherwise, the word “comprise” or variations such as “comprises” or“comprising”, will be understood to imply the inclusion of a statedinteger or group of integers but not the exclusion of any other integeror group of integers.

DISCLOSURE OF THE INVENTION

[0012] In accordance with the present invention there is provided astabilising arrangement characterised by a mounting member, at least oneforward truck supporting a forward pair of surface engaging members, andat least one rear truck supporting a rear pair of surface engagingmembers, each truck allowing biased rotation about a central axisthereof, the forward truck being mounted on the mounting member suchthat it projects forwardly thereof and the rear truck being mounted onthe mounting member such that it projects rearwardly thereof, thecentral axis of rotation of each truck being aligned with a longitudinalaxis of the mounting member, the mounting member being supportedsubstantially between the trucks and pairs of surface engaging member,whereby rotation of the mounting member about its longitudinal axis iscompensated for.

[0013] Preferably, the mounting of the trucks to the mounting member issuch that the central axis of rotation of at least one of the trucks isinclined from the horizontal as defined by the mounting member. Bothtrucks are preferably inclined in this manner.

[0014] Still preferably, the inclination of the or each truck is about8°.

[0015] Preferably, the forward and rear pairs of surface engagingmembers are spread at least about 150 mm apart.

[0016] Still preferably, an intermediate member is attached to themounting member in a pivotal manner whereby a weight may be supported onthe stabilising arrangement. In one form of the invention theintermediate member is fixed to another member by way of a resilientlybiased parallelogram link.

[0017] In accordance with the present in invention there is furtherprovided a suspension and steering arrangement for a vehicle, thesuspension and steering arrangement characterised by a mounting member,at least one forward truck supporting a forward wheel pair, and at leastone rear truck supporting a rear wheel pair, each truck allowing biasedrotation about a central axis thereof, the forward truck being mountedon the mounting member such that it projects forwardly thereof and therear truck being mounted on the mounting member such that it projectsrearwardly thereof, the central axis of rotation of each truck beingaligned with a longitudinal axis of the mounting member, the mountingmember being supported substantially between the trucks and wheel pairs,whereby rotation of the mounting member about its longitudinal axis iscompensated for.

[0018] Preferably, the mounting member is arranged to be pivotallyconnected to a means for steering the conveyance on which the suspensionand steering arrangement is provided. A flexibly resilient biasing meansis preferably provided within or attached to the mounting member suchthat the forward wheels are biased upwardly, and the rear wheelsdownwardly.

[0019] In one form of the present invention the flexibly resilientbiasing means is provided in the form of a radial polymeric spring.

[0020] Preferably, the mounting of the trucks to the mounting member issuch that the central axis of rotation of at least one of the trucks isinclined from the horizontal as defined by the mounting member. Bothtrucks are preferably inclined in this manner.

[0021] Still preferably, the inclination of the or each truck is about8°.

[0022] Preferably, the forward and rear pairs of surface engagingmembers are spread about 150 to 300 mm apart.

[0023] The term ‘truck’ is to be understood to encompass any arrangementwhich acts to cant the wheels off the vertical, longitudinal or bothaxes, thereby enhancing corner and camber negotiation of the steeringand suspension arrangement.

[0024] Still preferably, the trucks at least embody a centralising andshock absorbing pivot mechanism therein, either integrally orexternally.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The stabilising arrangement of the present invention will now bedescribed, by way of example only, with reference to three embodimentsin the form of a suspension and steering arrangement for a vehicle, andthe accompanied drawings, in which:

[0026]FIG. 1 is a side elevational view of a bicycle to which asuspension and steering arrangement for a vehicle, in accordance with afirst embodiment of the present invention is fitted;

[0027]FIG. 2 is an upper perspective view of the suspension and steeringarrangement of FIG. 1;

[0028]FIG. 3 is a side elevational view of the suspension and steeringarrangement of FIG. 1;

[0029]FIG. 4 is a side elevational view of only the mounting member andthe trucks of the suspension and steering arrangement of FIG. 1;

[0030]FIG. 5 is a side elevational view of the suspension and steeringarrangement of FIG. 1 shown with the forward truck and wheels biasedupwardly;

[0031]FIG. 6 is an upper perspective view of the suspension and steeringarrangement of FIG. 1 shown traversing an obstacle;

[0032]FIG. 7 is an upper perspective view of a suspension and steeringarrangement in accordance with a second embodiment of the presentinvention, shown without the steering member to which it would be fittedin use;

[0033]FIG. 8 is a forward upper perspective view of a suspension andsteering arrangement in accordance with a third embodiment of thepresent invention, shown without wheels provided thereon, the steeringmember being shown only in part;

[0034]FIG. 9 is a rear upper perspective view of the suspension andsteering arrangement of FIG. 8; and

[0035]FIG. 10 is an upper plan view of the suspension and steeringarrangement of FIG. 8.

BEST MODE(S) FOR CARRYING OUT THE INVENTION

[0036] In FIG. 1 there is shown a bicycle 10 comprising a frame 12, arear wheel 14, a drive means 16 of known form, a saddle post 18, asaddle 20, a gooseneck 22 and handle bars 24. The gooseneck 22 engagesthe handle bars 24 and is rotatably received through a hollow neck 26 ofthe frame 12, in known manner.

[0037] The gooseneck 22 extends through the neck 26 of the frame 12 andengages an elongate steering member 28 which replaces the forks of knownbicycles. The steering member 28 has provided thereon a stabilisingarrangement, in the form of a suspension and steering arrangement 30 inaccordance with a first embodiment of the present invention, and is bestseen in FIGS. 2 to 6.

[0038] The suspension and steering arrangement 30 comprises a mountingmember 32, a forward truck 34 supporting a forward pair of surfaceengaging members or wheels 36, and a rear truck 38 supporting a rearpair of surface engaging members or wheels 40.

[0039] The arrangement 30 further comprises a parallelogram link 42 anda pair of intermediate members 44. The intermediate members 44 arepivotally connected at their lower ends to the mounting member 32 at apivot point 46.

[0040] The parallelogram link 42 comprises, on each side of the steeringmember 28, an upper link member 48 and a lower link member 50. Eachmember 48 and 50 is pivotally attached to both the steering member 28and to one intermediate member 44. In this arrangement the intermediatemembers 44 may move in a parallel configuration with the steering member28.

[0041] The upper link members 48 project forwardly of the intermediatemembers 44 to which they're pivotally attached and have mountedtherebetween a base 52 of a piston or ram 54. The ram 54 extendsupwardly therefrom and is pivotally attached to an upper mounting member56 extending forwardly from the steering member 28. A flexibly resilientbiasing means, for example a compression spring 58, is provided aboutthe ram 54. The ram 54 and spring 58 absorb at least a portion of anyshocks passed through the wheeels 36 and 40, the mounting member 32, andparallelogram link 42 generally without passing these along the steeringmember 28.

[0042] The mounting member 32 has provided thereon an upwardly andforwardly projecting rim 60 on which flexibly resilient biasing means,for example a pair of springs 62, have one end thereof located. Theremaining ends of the springs 62 are attached to the upper link members48 and act to draw the forward wheels 36 upwardly about the pivot point46 when there is no load or weight on the arrangement 30, such as when arider (not shown) of the bicycle 10 pulls upwardly on the handle bars24. It is to be understood that this method of biasing the mountingmember 32 is one of a number of possible methods that could be employedwithout departing from the scope of the present invention. For example,a compression spring or springs may be provided between the steeringmember 28 and a point rearward of the pivot point 46 on the mountingmember 32, thereby achieving the same result.

[0043] In FIG. 4 the nature of the mounting of the trucks 34 and 36 tothe mounting member 32 is shown. The spreading of transverse axles 35 ofthe wheels 34 and 36 forward and back of the mounting member 32 has theeffect of enlarging the ‘footprint’ of the arrangement 30 relative to a‘traditional’ mounting which would see the trucks 34 and 36 mounteddirectly under the mounting member. 32.

[0044] The arrangement of FIG. 4 effectively accentuates the flexibilityof the trucks 34 and 36. Each truck 34 and 3G allows biased rotationabout its central axis, which in the arrangement 30 is aligned along alongitudinal axis of the mounting member 32 and, generally, the bicycle10, rather than substantially vertically as is the case in thearrangement of WO 98/57839 and traditional skateboards. Further rotationis provided for about a vertical axis passing though each truck 34 and36. This orientation of the trucks allows significant rotation of thewheel axles relative to both the longitudinal and vertical axis of eachtruck, thereby allowing the footprint to remain on the ground evenwhilst the bicycle 10 is undergoing tight turns, and even whilsttraversing uneven terrain, as can be seen in FIGS. 5 and 6.

[0045] In FIG. 4 a horizontal plane is shown by line A-A, essentiallydefined by the transverse axles 35 and the mounting member 32. Theinclination of the mounting of the trucks 34 and 36 to the mountingmember 32 can be seen in this Figure. Each truck is inclined at about 8°to the horizontal, this angle being designated X. This acts to lower thepivot point 46 relative to the axles 35 of the wheels 36 and 40 andaccentuates the stability of the arrangement 30 when turning, and whentraversing uneven terrain. It is envisaged that the angle X may beprovided reasonably up to 45°, although theoretically any angle of up to90° should function in accordance with the invention.

[0046] The axles 35 of the wheel pairs 36 and 40 are spread about 150 mmapart, although it is envisaged that a spread of up to 300 mm wouldstill function appropriately. However, the size of the “footprint” mustbe balanced against an ability to traverse bumps and the like without‘grounding’ the mounting member 32.

[0047] It is preferable that the pivot point 46 be located as close tothe line A-A as practical as this adds to the stability of thearrangement 30, particularly when turning.

[0048] The upper mounting member 56 and the parallelogram link 42 may belocated at any point with respect to the steering member 28 and stillfunction in accordance with the present invention. Further, thearrangement 30 may similarly be arranged as a ‘trailing link’ as opposedto the ‘leading link’ described hereinabove. In such a ‘trailing link’arrangement the parallelogram link 42 projects rearwardly of thesteering member 28.

[0049] In FIG. 7 there is shown a suspension and steering arrangement100 in accordance with a second embodiment of the present inventionsubstantially similar to the suspension and steering arrangement 30described hereinabove and like numerals denote like parts. The steeringmember to which the parallelogram link 42 is attached is not shown.

[0050] A lower end 102 of an intermediate member 104 is mounted on atransverse member 106 provided between the forward projections of theupper link members 48. An upper end 108 of the intermediate member 104is arranged to be mounted to the steering member (not shown) at a pointabove the level of the mounting of the parallelogram link 42. Thismounting is achieved by way of a flexibly resilient biasing means,preferably in the form of a radially flexibly resilient polymericmaterial. Such a biasing means is distinguished by a generally annularform with an outer radial surface and an inner radial surface, the outersurface being fixed to one member and the outer radial surface fixed toanother, whereby the rotation of the inner surface relative to the outersurface is flexibly and resiliently biased.

[0051] The pivot point 46 between the intermediate members 44 and themounting member 32 is provided with a radially flexilble resilientbiasing means such that the forward wheel pair 36 are biased upwardly,as in the embodiment of FIGS. 1 to 6, without the need for the pair ofsprings 62 or similar.

[0052] Further, the typical biasing means of the trucks 34 and 38 arereplaced with a radially flexible resilient biasing means, as describedhereinabove, and located about the longitudinal rotational axis of eachtruck 34 and 38. Each truck 34 and 38 is provided with an intermediatetransverse member 110 that engages the outer surface of the biasingmeans and to which a stub axle 112 from each wheel is attached. Theinner surface of the biasing means is attached to a member defining thecentral axis of the truck.

[0053] In FIGS. 8 to 10 there is shown a suspension and steeringarrangement 120 in accordance with a third embodiment of the presentinvention substantially similar to the suspension and steeringarrangement 100 described hereinabove and like numerals denote likeparts. The steering member to which the parallelogram link 42 isattached is again not shown.

[0054] A single intermediate member 44 is provided having a radiallyflexible resilient biasing means held within a lower end 122 and afurther radially flexible resilient biasing means held within an upperend 124 thereof. The lower end 122 is received within a recess 126 inthe mounting member 32. A pivot member extends transversely through therecess and engages an inner surface of the biasing means therebyproviding the pivot point 46 between the intermediate member 44 and themounting member 32.

[0055] The upper link members 48 again have a transverse member 106provided between their forward ends. However, a radial biasing means isprovided about the transverse member 106, the inner surface thereof. Inengagement therewith. The outer surface thereof being in engagement inthe upper end 124 of the intermediate member 44. In such a manner theshock absorbing characteristics of the ram 54 and spring 58 of thearrangement 30 are achieved wihout the need for another remote mountingto the steering member 28 as provided by the upper mounting member 56.Similarly, the intermediate member 104 of the arrangement 100 is notrequired.

[0056] It is envisaged by the inventor that the parallelogram link 42may be replaced by its functional equivalent without departing from thespirit and scope of the present invention.

[0057] It is further envisaged that an arrangement in accordance withthe present invention may be utilised as a surface engaging element forthe stabilising arrangements employed, for example, on heavy machineryand equipment. Such applications will include cranes and diggingequipment employing rams with surface engaging elements on the lowerends thereof. The wheels of the arrangements 30, 100 and 120 describedhereinabove may be replaced with other more suitable surface engagingmeans.

[0058] In such applications the same features that provide the surfaceholding ability of the arrangements 30, 100 and 120 provide thearrangement with an ability to adapt to the configuration of a surface,be it undulating or loose, in a stable manner. It is envisaged that theintermediate member 44 may be attached to the piston member of a ram inthe same manner as it is described above as being attached to thesteering member 28. Alternatively, the ram may be attached to themounting member 32 directly.

[0059] It is still further envisaged that the surface engaging elementapplications of the arrangement of the present invention go beyondstabilising heavy equipment and may find application in othercircumstances requiring a stable ground engaging element.

[0060] The stabilising arrangements 30, 100 and 120 describedhereinabove are to be understood to be an illustration of principleonly. The same or similar functions may be achieved through the use oflinkages, mechanisms or transposed elements of the spirit and nature ofthose of the embodiment described, in one or more arrangements orcombinations thereof in any area or location within or on a vehicle. Assuch, modifications and variations such as would be apparent to theskilled addressee are considered to fall within the scope of the presentinvention.

1. A stabilising arrangement characterised by a mounting member, atleast one forward truck supporting a forward pair of surface engagingmembers, and at least one rear truck supporting a rear pair of surfaceengaging members, each truck allowing biased rotation about a centralaxis thereof, the forward truck being mounted on the mounting membersuch that it projects forwardly thereof and the rear truck being mountedon the mounting member such that it projects rearwardly thereof, thecentral axis of rotation of each truck being aligned with a longitudinalaxis of the mounting member, the mounting member being supportedsubstantially between the trucks and pairs of surface engaging member,whereby rotation of the mounting member about its longitudinal axis iscompensated for.
 2. A stabilising arrangement according to claim 1,wherein the mounting of the trucks to the mounting member is such thatthe central axis of rotation of at least one of the trucks is inclinedfrom the horizontal as defined by the mounting member.
 3. A stabilisingarrangement according to claim 2, wherein both trucks are inclined inthis manner.
 4. A stabilising arrangement according to claim 2, whereinthe inclination of the or each truck is about 8°.
 5. A stabilisingarrangement according to claim 1, wherein the forward and rear pairs ofsurface engaging members are spread at least about 150 mm apart.
 6. Astabilising arrangement according to claim 1, wherein an intermediatemember is attached to the mounting member in a pivotal manner whereby aweight may be supported on the stabilising arrangement.
 7. A stabilisingarrangement according to claim 6, wherein the intermediate member isfixed to another member by way of a resiliently biased parallelogramlink.
 8. A suspension and steering arrangement for a vehicle, thesuspension and steering arrangement characterised by a mounting member,at least one forward truck supporting a forward wheel pair, and at leastone rear truck supporting a rear wheel pair, each truck allowing biasedrotation about a central axis thereof, the forward truck being mountedon the mounting member such that it projects forwardly thereof and therear truck being mounted on the mounting member such that it projectsrearwardly thereof, the central axis of rotation of each truck beingaligned with a longitudinal axis of the mounting member, the mountingmember being supported substantially between the trucks and wheel pairs,whereby rotation of the mounting member about its longitudinal axis iscompensated for.
 9. A suspension and steering arrangement according toclaim 8, wherein the mounting member is arranged to be pivotallyconnected to a means for steering the conveyance on which the suspensionand steering arrangement is provided.
 10. A suspension and steeringarrangement according to claim 8, wherein a flexibly resilient biasingmeans is provided within or attached to the mounting member such thatthe forward wheels are biased upwardly, and the rear wheels downwardly.11. A suspension and steering arrangement according to claim 10, whereinthe flexibly resilient biasing means is provided in the form of a radialpolymeric spring.
 12. A suspension and steering arrangement according toclaim 8, wherein the mounting of the trucks to the mounting member issuch that the central axis of rotation of at least one of the trucks isinclined from the horizontal as defined by the mounting member. 13.(CANCELED)
 14. (CANCELED)
 15. (CANCELED)
 16. (CANCELED)